Eight patients at a sweltering nursing home died after Hurricane Irma knocked out the air conditioning, raising fears Wednesday about the safety of Florida’s four million senior citizens amid power outages that could last for days.

Hollywood police Chief Tom Sanchez said investigators believe the deaths at the Rehabilitation Center at Hollywood Hills were heat-related, and added: “The building has been sealed off and we are conducting a criminal investigation.” He did not elaborate.

He said investigators have not ruled out anything, including carbon monoxide from generators. The chief also said investigators will look into how many windows were open in the nursing home, where the air conditioning wasn’t working.

“It’s a sad state of affairs,” Sanchez said. “We all have elderly people in facilities, and we all know we depend on those people in those facilities to care for a vulnerable elderly population.”

Gov. Rick Scott called on Florida emergency workers to immediately check on all nursing homes to make sure patients are safe, and he vowed to punish anyone found culpable in the deaths. “This situation is unfathomable,” he said.

“I am demanding answers,” he tweeted.

The home said in a statement that the hurricane had knocked out a transformer that powered the air conditioning.

The five women and three men ranged in age from 70 to 99.

The deaths came as people trying to put their lives back together in hurricane-stricken Florida and beyond confronted a multitude of new hazards in the storm’s wake, including tree-clearing accidents and lethal fumes from generators.

At least 25 people in Florida have died under Irma-related circumstances, and six more in South Carolina and Georgia, many of them well after the storm had passed.

Deaths caused by carbon monoxide fumes

At least five people died and more than a dozen were treated after breathing carbon monoxide fumes from generators in the Orlando, Miami and Daytona Beach areas. A Tampa man clearing fallen trees died after the chainsaw he was using kicked back and cut his carotid artery.

Nursing homes in Florida are required by state and federal law to file an emergency plan that includes evacuation plans for residents. County officials released documents showing that the Hollywood facility was in compliance with that regulation and that it held a hurricane drill with its staff in October.

Calls to the owner and other officials at the Hollywood home were not immediately returned, but the facility’s administrator, Jorge Carballo, said in a statement that it was “co-operating fully with relevant authorities to investigate the circumstances that led to this unfortunate and tragic outcome.”

Through a representative, Carballo told the SunSentinel newspaper that the home has a backup generator but that it does not power the air conditioning.

The facility was bought at a bankruptcy auction two years ago after its previous owner went to prison for Medicare fraud, according to news reports at the time of the sale.

The Centers for Medicare and Medicaid Services, which regulates nursing homes, gives the Hollywood centre a below-average rating, two stars on its five-star scale. But the most recent state inspection reports showed no deficiencies in the area of emergency plans.

More than 100 patients evacuated from facility

In Hollywood, after responding to three early morning calls Wednesday about patients in distress, firefighters went through the facility, found three people dead and evacuated more than 150 patients to hospitals, many on stretchers or in wheelchairs, authorities said. By the afternoon, five more had died.

Patients were treated for dehydration, breathing difficulties and other heat-related ills, authorities said.

Florida Power & Light said it had provided power to some parts of the nursing home but that the facility was not on a county top-tier list for emergency power restoration.

The Sea Breeze mobile home community in the Florida Keys was entirely levelled by Hurricane Irma’s violent winds and subsequent storm surge. (Sylvia Thomson/CBC)

Florida, long one of America’s top retirement destinations, has the highest proportion of people 65 and older of any state — one in five of its 20 million residents.

According to the Florida Health Care Association, which represents most of Florida’s nursing homes, “Approximately 150 facilities out of the nearly 700 facilities in the state do not currently have full power services restored.”

Air conditioner not working

At the Hollywood nursing home, Jean Lindor, a kitchen worker, said through a Haitian Creole translator that the air conditioner had not been working since the storm and it had been hot inside.

Paulburn Bogle, a member of the housekeeping staff, said the place had been hot but manageable the past few days. The staff used fans, put cold towels and ice on patients and gave them cold drinks, he said.

Broward County medical examiner Dr. Craig Mallak said his office had received the bodies of three of the victims — two women age 71 and another who was 78 — for autopsies.

“It’s going to be tough to tell how much was the heat and how much of it was they were sick already,” Mallak said.

Flora Mitchell arrived at the home trying to find out what happened to her 58-year-old sister, Vonda Wilson, a stroke patient who lived there for about 10 years. She said she last heard from her sister two days ago and found out the air conditioning was not working.

“We need to know what happened to her,” she said. “They haven’t told us anything.”

1/3 of Floridians without electricity

Elsewhere around the state, a Coral Gables apartment building was evacuated after authorities determined a lack of power made it unsafe for elderly tenants.

And at the huge, 15,000-resident Century Village retirement community in Pembroke Pines, more than half the residential buildings had no power Wednesday afternoon. Rescue crews began going door to door in the 34 C heat to check on people, and a water, ice and meal distribution plan was put into effect.

Roughly half of Florida’s population is still without power following Hurricane Irma. (Chip Somodevilla/Getty Images)

The number of people without electricity in the steamy late-summer heat dropped to 6.4 million — about a third of Florida’s population. Utility officials warned it could take 10 days or more for power to be fully restored. About 13,000 people remained in shelters across the state.

In the battered Florida Keys, meanwhile, county officials pushed back against a preliminary estimate from the Federal Emergency Management Agency that 25 per cent of all homes in the Keys were destroyed and nearly all the rest were heavily damaged.

“Things look real damaged from the air, but when you clear the trees and all the debris, it’s not much damage to the houses,” said Monroe County commissioner Heather Carruthers.

The Keys felt Irma’s full fury when the hurricane roared in on Sunday with 210-km/h winds. But the extent of the damage has been an unanswered question for days because some places have been unreachable.

Trump to visit Florida

U.S. President Donald Trump’s homeland security adviser, Tom Bossert, said the federal government is working to help Florida Keys residents secure shelter through rental assistance, hotels or pre-manufactured housing. Trump plans to visit Florida on Thursday.

Officials say 25 per cent of homes in the Florida Keys have been destroyed and the area’s only major road is partially closed because of damage. (Carlos Barria/Reuters)

While nearly all of Florida was engulfed by the massive storm, the Keys — home to about 70,000 people — appeared to be the hardest hit. Drinking water and power were cut off, all three of the islands’ hospitals were closed, and gasoline was extremely limited.

Search-and-rescue teams made their way into the more distant reaches of the Keys, and an aircraft carrier was positioned off Key West to help. Officials said it was not known how many people ignored evacuation orders and stayed behind in the Keys.

Crews also worked to repair two washed-out, 90-metre sections of U.S. Route 1, the only highway that runs through the Keys, and check the safety of the 42 bridges linking the islands.

The Lower Keys were still off-limits, with a roadblock in place where the highway was washed out.